1. Field of the Invention
This technology relates to a configurable interconnection coupling interconnects, and a programmable logic device with such configurable interconnections.
2. Description of Related Art
In the field programmable gate array (FPGA) device described by U.S. Pat. Nos. 7,307,451 and 7,511,523; and U.S. Patent Application Publication No. 2007/0146012, a phase change material storage element is part of a control unit that stores settings of the configurable interconnections of the FPGA. The control unit is distinct from the actual configurable interconnections of the FPGA. Every time the FPGA is turned on, the contents of the control unit are read, and used to determine the settings of the configurable interconnections of the FPGA.
In the programmable matrix of an FPGA device described by U.S. Pat. No. 7,499,315 and U.S. Patent Application Publication No. 2006/0171194, a phase change material storage element is again part of a control cell, distinct from the actual configurable interconnections of the FPGA. Also discussed is the use of anti-fuse devices that directly connect a vertical interconnect and a horizontal interconnect. Such anti-fuse devices are programmed via signals through the very same vertical interconnect and horizontal interconnect that are coupled by the anti-fuse device. Because programming circuitry for the anti-fuse devices is connected to the same interconnects for logical operations, the interconnects have an additional RC delay associated with the programming circuitry load.